| In order to deal with the consumption of fossil energy and environmental pollution,more and more attention has been paid to new energy vehicles.Pure electric vehicle has the natural advantages of reducing energy consumption and environmental pollution,which makes it more and more popular.If we want to achieve overtaking by pure electric vehicle in the curve,we should conduct in-depth research on energy management,power transmission framework and power transmission control.In order to improve the power performance of pure electric vehicle,this paper studies the active cooperative control strategy of pure electric vehicle powertrain system with EM-CVT transmission in the environment of vehicle cluster.This paper focuses on the following three aspects: vehicle power prediction,vehicle powertrain active collaborative control strategy formulation and strategy test and verification.The contents are as follows:1)The necessity of research on active cooperative control of vehicle powertrain system is explained.The research status of vehicle driving rule,powertrain system control strategy and application of Internet of vehicles technology at home and abroad is analyzed.The problem of combination of Internet of vehicles technology and vehicle powertrain control is discussed.Based on the analysis and discussion of the above problems,the research route and content are proposed.2)The object of this paper is established and its structure is analyzed.The driving motor model,EM-CVT model,power battery model and vehicle dynamics model are built with Matlab / Simulink.3)Based on the theory of traffic flow,this paper analyzes the vehicles’ characteristics of the following,gap acceptance and lane change in the process of driving,puts forward a three-lane vehicle following model in the environment of vehicle cluster,and describes the driving behavior of vehicles in a unified way.Based on the three-lane car following model,a vehicle dynamic demand prediction algorithm is proposed.4)Based on the working characteristics of the vehicle powertrain system,a passive control strategy of the powertrain system is designed,which takes the vehicle performance of dynamic and economy into account.On the basis of this strategy,the active cooperative control strategy of vehicle powertrain system is developed.5)With Ni PXI as the core,the driver in the loop real-time simulation system is built.According to the real traffic scene,a test case is designed to test and verify the active cooperative control strategy of vehicle powertrain system.The test results show that the strategy can release the backup power in time according to the driver’s driving demand,improve the vehicle’s dynamic performance,reduce the EM-CVT work intensity and extend its service life on the basis of ensuring the original economy of the vehicle. |
